naruto can create organs, that's pretty scary.
as was said before kakashi needs the sharingan to do shit, all his lightning cutter/chidori stuff needs a sharingan to be effective, it's why he taught it to saskae.
also i'm sure his genjutsu defense and offense is lowered
even without it, he was already a "genius" as was his father, who was also a genius, i guess that's what passes down, his father was strong like a sannin too.
just think kakashi won't keel over everytime now he's in a fight, he's always weak cuz his non uchiha body is supplying chakra to a sharingan, he's always just falling over from chakra exhaustion, even without using mangekyo, just the sharingan alone drains him dry.
hell didn't he get 2 powerups. one from naruto's shroud that affected everyone and another from the nine tails (when he gave chakra to guy and kakashi).
he seemed pretty pro at swinging zabusa's claymore, he'll probably fall back on that and his smarts, he also still has the encyclopedia of jutsu he's sharingan'd he just can't steal new stuff.